1. Field of the Invention
This invention relates to a recording apparatus such as a printer, and particularly to a recording apparatus for effecting recording with the gap between a recording material and recording means such as a recording head changed properly when recording is to be effected on recording materials having various thicknesses.
2. Related Background Art
There have heretofore been various recording materials on which recording is effected by a recording apparatus such as a printer. They include compact and thick recording materials such as CD-R, DVD and cards. Hereinafter there will be collectively called a “compact disc” or “CD”. When in the existing versatile printer, printing is to be effected on the aforementioned recording material, if a conveying path for slip paper (leaf paper) is used, there will arise the problems that (1) conveyability is not good due to rigidity, (2) injuries occur, and (3) conveyance cannot be done because of the distance between conveying rollers. So, these problems are coped with by using a tray and using a path differing from the conveying path for slip paper.
The tray has a greater thickness than ordinary slip paper and therefore, it is necessary to nip it between a pair of conveying rollers, and secure a gap between a recording head and a recording medium. As a means therefore, an operating lever is provided in the printer, and the pressing of a conveying member is released in operative association of the movement of the operating lever. A user then inserts the tray into a predetermined position and positions it, whereupon the user operates the operating lever and presses the conveying member. Further, the user elevates a carriage carrying the recording head thereon, by the operating lever, to thereby secure the gap between the recording head and the recording medium. Eccentric cams are provided on the opposite ends of a guide shaft for scanning the carriage, and the eccentric cams are operatively associated with the operation of the operating lever. Also, the rotated position of the eccentric cams is detected by the use of a sensor or the like to thereby detect a plurality of stages of gap positions.
Also, it is practiced to effect printing without particularly effecting the detection of the position of the recording medium such as the CD, or to directly detect the position of a white portion within a CD printing range by a sensor carried on the carriage, and effect printing.
The above-described example of the prior art, however, has suffered from the following problems.
In the case of a construction in which the position of the carriage is accurately grasped to thereby improve the accuracy of printing, a linear sensor provided on the carriage side is often used to detect the number of the bars of a code strip on which a plurality of bars are printed, during the scanning of the carriage, to thereby detect the position of the carriage.
When in such a construction, the eccentric cams on the opposite ends of the guide shaft are rotated to thereby move up and down the carriage with the guide shaft, if the amount of change in the ordinary printing height of the carriage and the printing height when the carriage has been moved uppermost is great, the code strip comes off from the sensor for detecting the position of the carriage and it becomes impossible to detect the position of the carriage.
In order to avoid this problem, use has been made of a mechanism for raising the opposite ends of the code strip in conformity with the upward movement of the guide shaft, but this requires many parts, and not only has increased costs, but also has complicated the mechanism and has sometimes spoiled the reliability of the apparatus.